How to pronounce "teal"

I want to tell you a love story.

But it doesn't have a happy ending.

Once upon a time, I was a stubborn five-year-old

who decided to become a marine biologist.

Thirty-four years, 400 scuba dives and one PhD later,

I'm still completely enamored with the ocean.

I spent a decade working with fishing communities

in the Caribbean,

counting fish, interviewing fishermen,

redesigning fishing gear and developing policy.

I've been helping to figure out what sustainable management can look like

for places where food security, jobs and cultures

all depend on the sea.

In the midst of all this, I fell in love.

With a fish.

There are over 500 fish species that live on Caribbean reefs,

but the ones I just can't get out of my head

are parrotfish.

Parrotfish live on coral reefs all over the world,

there are 100 species,

they can grow well over a meter long

and weigh over 20 kilograms,

but that's the boring stuff.

I want to tell you five incredible things about these fish.

First, they have a mouth like a parrot's beak,

which is strong enough to bite coral,

although mostly they're after algae.

They are the lawn mowers of the reef.

This is key, because many reefs are overgrown with algae

due to nutrient pollution from sewage and fertilizer

that runs off of land.

And there just aren't enough herbivores like parrotfish

left out on the reefs

to mow it all down.

OK, second amazing thing.

After all that eating, they poop fine white sand.

A single parrotfish can produce over 380 kilograms

of this pulverized coral each year.

Sometimes, when scuba diving,

I would look up from my clipboard

and just see contrails of parrotfish poop raining down.

So next time you're lounging on a tropical white-sand beach,

maybe thank of parrotfish.

(Laughter)

Third, they have so much style.

Mottled and striped, teal, magenta,

yellow, orange, polka-dotted,

parrotfish are a big part of what makes coral reefs so colorful.

Plus, in true diva style,

they have multiple wardrobe changes throughout their life.

A juvenile outfit,

an intermediate getup,

and a terminal look.

Fourth, with this last wardrobe change comes a sex change from female to male,

termed sequential hermaphroditism.

These large males then gather harems of females to spawn.

Heterosexual monogamy is certainly not nature's status quo.

And parrotfish exemplify some of the beauty

of diverse reproductive strategies.

Fifth, and the most incredible,

sometimes when parrotfish cozy up into a nook in the reef at night,

they secrete a mucus bubble from a gland in their head

that envelops their entire body.

This masks their scent from predators

and protects them from parasites,

so they can sleep soundly.

I mean, how cool is this?

(Laughter)

So this is a confession of my love for parrotfish

in all their flamboyant,

algae-eating, sand-pooping, sex-changing glory.

(Laughter)

But with this love comes heartache.

Now that groupers and snappers are woefully overfished,

fishermen are targeting parrotfish.

Spearfishing took out the large species,

midnight blue and rainbow parrotfish are now exceedingly rare,

and nets and traps are scooping up the smaller species.

As both a marine biologist and a single person,

I can tell you,

there aren't that many fish in the sea.

(Laughter)

And then, there's my love for their home,

the coral reef,

which was once as vibrant as Caribbean cultures,

as colorful as the architecture,

and as bustling as carnival.

Because of climate change,

on top of overfishing and pollution,

coral reefs may be gone within 30 years.

An entire ecosystem erased.

This is devastating,

because hundreds of millions of people around the world

depend on reefs for their nutrition and income.

Let that sink in.

A little bit of good news

is that places like Belize, Barbuda and Bonaire are protecting these VIPs --

Very Important Parrotfish.

Also, more and more places are establishing protected areas

that protect the entire ecosystem.

These are critical efforts, but it's not enough.

As I stand here today,

only 2.2 percent of the ocean is protected.

Meanwhile, 90 percent of the large fish,

and 80 percent of the coral on Caribbean reefs,

is already gone.

We're in the midst of the sixth mass extinction.

And we, humans, are causing it.

We also have the solutions.

Reverse climate change and overfishing,

protect half the ocean

and stop pollution running from land.

But these are massive undertakings

requiring systemic changes,

and we're really taking our sweet time getting around to it.

Each of us can contribute, though.

With our votes, our voices, our food choices,

our skills and our dollars.

We must overhaul both corporate practices

and government policies.

We must transform culture.

Building community around solutions

is the most important thing.

I am never going to give up

working to protect and restore this magnificent planet.

Every bit of habitat we preserve,

every tenth of a degree of warming we prevent,

really does matter.

Thankfully, I'm not motivated by hope,

but rather a desire to be useful.

Because I don't know how to give an honest talk

about my beloved parrotfish and coral reefs

that has a happy ending.

Thank you.

(Applause)